Reel antenna



Dec. 23, 1952 T. R. FINKE 2,623,175

REEL ANTENNA Filed March 25, 1949 2"SHEETS SHEET' l V INVENTOR. T/IMDORER. Frzv/cfi A TTOR/VEY Dec. 23,1952 T. R. FINKE 2,623,175

' REEL ANTENNA Filed March 25, 1949 2 SHEETS-SHEET 2 yevzl llllllINVENTOR. 771500035 1?.F/A/Kfi ATToIZA/Ey Patented Dec. 23, 1952 REELANTENNA Theodore R. Finke, Euclid, Ohio, assignor to rhe :RadiartCorporation, Cleveland, .0hio,:a .cor-

porationof Ohio Application .Marc'h25, 19.49, 'Serial'No. 83,503

This invention relates, asin'dicat'ed, to "areel antenna.

Aprimary object of "the invention is'to provide "a reel antenna having adrum in which the antenna cable is wound,'the drumhaving'cliaracteristics enabling it to "functi-oneffe'ctively in thewinding and unwinding of "the cable.

Another object of the invention is "to provide a reel antenna having acable winding drum which is designed to provide space for "an overloadclutch, to thereby reduce the overall dimensions'or thickness of theassembly "to a "minimum.

Another obje'ctof the inventionis to provide a reelantennahaving-acable'winding drum and anoverload'clutch of'novel design,through which the drum-is driven.

Another object of the invention 'is "to provide a reel antenna,embodying a cable winding'drum and drum cover in which the antenna cableis'completely enclosed, andfrom whichthecable is fed in a smoothandpositive manner.

A further object of theinvention is to provide a reel antenna embodyinga cable windingdrum and an overload clutch for driving thedrum,"'utilizing a maximum torque in thedrive.

A further obl'ect'of the inventionis'toprovide a reel antenna havinga'casing of novelysymmetrical design, enabling it to be-mounted ateither side ofan automobile.

-'A still further object'ofthe invention: is toprovide a compacteasilyhandled unit, consisting 'of a-mast antenna,-a'reel or'drum forextending or collapsing the "antenna, a casing for 'efiiciently housingthe drum, and a bracket for supporting the unit on an automobile.

Other objectsand'advanta'ges of the invention will beapparentduring thecourse of the following description.

In the accompanying drawinga'f-orming apart ofthis specification, and inwhich like numerals are employed to designate like parts throughout'thesame,

Fig. lis a sideelevational viewo'fa reel antennasembodying the principalfeatures of the invention, and showing, in'broken lines, the antennamast in fully extended condition;

Fig- .2 is a viewwof-the antenna, as viewed from the leftside of Fig. 1;

Fig. :3 is a'vertical sectional'view through the drum casing, with theelements within the-casing 2 reel and reel casing, with the casing coverremoved;

Fig. 6 is a plan view of the drum or reel cover, with the cover blockremoved;

Fig. '7 is a fragmentary cross-sectional view, taken on the'line 11-ofFig.5;

Fig. 8 is-a-fragmentarycross-sectional view, on a greatly enlargedscale, taken-on-the line 8--8 of Fig. 2.

Fig. 9 is an-elevational view'of one sideor-end of' 'thecable drum;

Fig. 10 is a fragmentary cross-sectional view, taken-on the line il0|'0of'Fig.9;

Fig. 1-1 is an'enlarged detail of a p-ortion o'f Fig. 9;

Fig. 12 is across-sectional-view, taken nn'the line I2l2 of Fig-6, butshowing also asection through the drum cover block;

Fig.'13 is across-sectional view, taken-on the line |3|3 of Fig.6, and

Fig. 14 is a fragmentary perspective view, showing means forinterlocking the parts of the casing.

Referring more particularly to the drawings, the antenna will be seen'to comprise a, casing comprising a baseorbottom [of generally:pearshaped contour having an offset peripheral fiange 2, and a cover ortop 3, of substantially-the same contour and depth as the bottom I theperipheral edge .of which rests -on the shoulderor ledge 4 formed by theofisettingof the flange 2 of ithe bottomof .thecasing.

A portion of the shoulder '4 is removed to provide-a slot -5 (Fig. 14)for the reception :of a tongue 6 of the casing .top 3, .:forinterlocking theseparts-of the casing togetheriat this point. The .topor upperedge I ofithe slotl5, as viewed in .Fig. 14, issubstantiallyhushwith .thejledge or shoulder-l.

Thelmembersl and 3 otthenasingare formed in their upper ends to providea -circular: opening 8, for a purpose to be presentlydescribed.

Disposed within .the .case which has been .1 described, is an-antennareel or drum, consisting of a drum cover 9, a cover-block llhand a cabledrum II.

The drum cover-9 is-of substantially'the'same contour as the baseorbottom lot the casing, so as-to fit snugly in the 1atter,-and is=preferably molded, in a single piece, of a plastic insulating material,such for example, asa general purpose phenolic orthermoplastic plasticmaterial. It is molded to provide-a surface'IZ, and an upperend portion15 whichisof"considerablygreater thickness than the body ofthedrum'cover. Three circumferentially-spaced openings [6 extend throughthe drum cover, for the purpose of lightening the cover. The drum coveris also provided with a nut H (Figs. 6 and 8) for the reception of ascrew Ila for securing the drum cover to the casing bottom I. The drumcover also has an opening 18 which extends through the cover, laterallyspaced openings 20 which extend through the portion I of the drum coverand have counterbores 2| at their lower ends, and an opening 22 whichextends through the portion 15. The drum cover is also provided with acable groove 24 which begins at a point 25 adjacent the lower end of thedrum cover and lies below the surface [2, a portion of this groove beingconcentric with the opening l8. This groove extends through the portioni5 of the drum cover and communicates with the base of a recess 26 inthe upper end of the portion IS. The groove is of uniform width, and thebase thereof is curved as shown in Fig. 13. The portion I5 of the drumcover has divergent walls 21 and 23 which extend from the upper edges ofthe groove 24, as best shown in Figs. 6, 12 and 13.

The cover block I0, which is likewise molded, in a single piece, from aplastic material, overlies the portion l5 of the drum cover, and has asemi-circular recess 36 therein which coacts with the recess 26 in thedrum cover to form a circular opening which is in alignment or registrywith the opening 8 of the casing. The cover block ii] is also providedwith threaded openings 3| which register with the openings 29 in thedrum cover, and with an opening 32 which registers with the opening 22in the drum cover. It also has a projection [0a which nests in theopening or recess formed by the walls 21 and 28 of the drum cover, andwhich projection has walls b, and I60 which engage the walls 21 and 28respectively, leaving a passageway of square cross-section (Fig. 12)formed by the groove 24 and projection lila.

The cover block I6 is secured to the drum cover by means of screws 33,the screws passing through the aligned openings 20 and 3| with the headsof the screws lying in the counterbores 2i and the ends of the screws inthreaded engagement with the openings 3 I.

The cable drum II is also molded, in a single piece, from a plasticmaterial, and consists of a .pair of spaced annular portions 35 and 36,which are interconnected at one end,.as at 31, to form'an open endedannular cable groove, 38, a central hub portion 39 having an opening 46in axial alignment with the opening l8 in the drum cover, a web 4| whichinterconnects the annular portion 35 and hub portion 39, and reinforcingribs 42 which extended radially from the hub 39 to the annulus 35. Fourvopenings 43, located intermediate the spaces between the ribs 42,extended through the web 4|, and serve to lighten the drum. The radiallyouter face of the annulus '35 and the radially inner face of the annulus36 are molded to provide serrations 44 having sharp edges, theseserrations serving a purpose to be presently described.

The cable drum is supported in close proximity to the surface l2 of thedrum cover, with the open end of the groove 38 thereof facing saidsurface, and is connected to the drum cover by means of a sleeve,preferably formed from brass rod, to provide a base portion 45 whichextends through the opening I 3 in the drum cover, a radial flange 46which is interposed between the surface v l2 and the hub portion of thedrum, a bearing portion 41 which passes through the opening 40 in thedrum, and an externally threaded portion 48, to which a lock nut 56 issecured. The sleeve is maintained in assembled relation with the drumcover by means of a split retaining ring 5|, which is snapped within agroove 52 in the sleeve and bears against a thrust washer 53. The washer53 bears against the base of the drum cover.

Disposed between the lock nut 50 and the hub portion 39 of the drum is aclutch consisting of an annular clutch plate 55 having notches 56 intowhich the reinforcing ribs 42 extend, and a multiplicity ofcircumlerentially-spaced cupshaped embossments 51, and a clutch hub 58which is threadedly secured to the portion 48 of the sleeve and hassecurely iastened thereto a clutch spring 59 comprising an annular sheetmetal member having radially-extending spring arms 60 provided withcup-shaped embossments 6! which are adapted to nest with the embossments5! when the clutch spring and clutch plate are engaged, as they areduring normal operation of the reel. The tension of the clutch spring onthe clutch plate may be adjusted by adjustment of the clutch hub 53along the threaded portion 48 of the sleeve, the nut 50 serving to lockthe clutch hub in adjusted position. The function of this clutch will bedescribed in corinection with the operation of the antenna ree The reelfurther includes a cable 62, one end of which is secured to the cabledrum II at the bottom of the groove 38, as shown in Figs. 9 and 10. Thecable is a flexible cable of the wound Monocoil type having a looseinternal stiffening wire. The cable is wound spirally about the drum,within the groove 38, the width of this groove being such that only asingle row of convolutions of the cable can be wound about the drum,thereby precluding the possibility of con- Volutions of the cableslipping over each other. The cable emerges from the drum and passesdirectly into the groove 24, at the point 25, emerging from the grooveinto the opening formed by the recesses 36 and 26, and thence throughthe opening 8 in the casing. The outer end of the cable is connected tothe uppermost section 63 of the antenna mast. The antenna mast furtherincludes a section 64 in which the section 53 is slidable, a sectlon 65in which the section 64 is slidable, and a section 66 in which thesection 55 is slidable. The section 66 is slidable in a sleeve 6'! whichis supported in an in sulator bushing 68 rigidly mounted in the upperend of a shielding tube 69. Disposed within the tube 69 is a tube iii,the upper end of which bears against the lowerend of the sleeve 61, andthe lower end of which is supported in a rubber insulator H which issecured within the lower end of the tube 69. The cable 62 passes throughan opening in the insulator H and through the tube 10, sleeve 67, andsections 66, 65 and 54 of the antenna mast. The insulator II has aportion 72 of reduced diameter, which extends into the circular openingformed by the semi-circular recesses 30 and 26.

The casing l, 3 of the antenna reel is secured to a supporting bracket13, as by means of a screw 14, which extends through the openings 32 and22, and is threadedly secured to the bracket, as shown in Fig. 8. Thebracket has an upper portion of arcuate cross-section which embraces thelower end of the shielding tube 69 and is rigidly secured to said tube.In this way,

aoza'rn the bracket, shielding tube and reel casing are assembledtogetheras a unit. The bracket may be secured to the automobile adjacentone .of the corner posts thereof.

The lead-in from the antenna is indicated by reference numeral T5, theshielding of this leadin being soldered as at it to a tube H, which isriveted or otherwise secured to the bracket '53. The lead-in has aterminal 18 (Fig. 3), which is connected to the tube H3. The usualinsulator sleeves l9 and 3b are provided at the point where the sleeve'61 passes through the body 8| of the automobile.

The antenna drum may be actuated manually, as by a hand wheel 82, orthrough a flexible cable, or by means of a motor. The handwheel 82, inthis case, is provided with a shaft t3 having a slotted end throughwhich a pin 84 extends, the pin at being mounted in the sleeve is (Fig.8). The shaft 33 is rotatable in a sleeve 85 which is mounted on asupport plate The plate 83 is secured to the bracket 13 by means ofscrews 81. Rotation of the handwheelfi? thus effects rotation of thedrum l 1 through the intermediary of the shaft 83, pin fit, sleeve i8,and clutch 59 and 55.

The operation of the reel will be readily understood from the foregoingdescription. Upon rotation of the sleeve 63 in one direction, the drumII will be driven through the intermediary of the clutch, therebycausing the cable 62 to be .unreeled from the drum and projected out ofthe drum cover and casing through the groove 24 and opening formed bythe recesses 33 and 26, thereby causing the antenna mast to be extended.

The serrations 44 of .the drum act in a manner similar to gear teeth,the serrations meshing with and engaging the windings of the cable.

When the antenna drum is driven, the inertia or initial resistance tomovement set up by the cable causes the coil of the cable to expand andthereby the windings of the cable snugly engage the serrations l l. Bythus engaging the serrations, the cable is forced out of the drum byforces applied to the cable through the serrations at the point wherethe cable emerges from the drum. The serrations prevent slippage of thecable in the drum as the cable meets resistance in raising the antenna.With slippage of the cable thus prevented, the cable propelling force isnot transmittedthroughout the length of the cable from the point offastening, but is transmitted from the actual point where the cableenters or leaves the drum. The serrations also aid in holding the cableat right angles to the direction of depth ofthe cable groove in thedrum, and in this way, any'tendency of the cable to buckle is obviated.

The antenna mast may also be extended or collapsed by manually movingthe antenna mast. When the antenna is thus directly moved, the cable, byengaging the serrations of the drum, will cause the drum to rotate. Asthe drum begins t'o'rotate, the cable is wound up by the drum as fast asit is pushed into the drum, and unwound as fast as itis pulled out ofthe drum. This driving of'the drumthrough the serrations preventsjamming of the cable in'the cable groove of-the drumfand is in'contrastto "the action of the cable in asmo'o'th, unserrated groove, whichpermits the cable tobuckle'in the groove when pushed, due to'the drumnot rotating and acceptingthe cable as fast as it is supplied to thedrum.

Due to the fact that the drum bearing hub is on the same side andadjacent to the coverbearing support hub, a very rigid mountingbetweenthe drum'and drum coveris'provided, excessive tolerance build-up, suchas is characteristic of existing or conventional drum and drum coverassemblies, is eliminated, and the effect of molding shrinkage andwarping is minimized.

'By having the supporting web 4! on the end of the drum adjacent thedrum cover, space is available for the clutch components. This allowsplacing of the clutch in the open where. it is easy of access forassembly and repairs. Also, the supporting web is close to the open endof the cable groove in the drum, at which point the operating forcesinvolved are greatest.

The reinforcing ribs of the drum serve as keys to hold the clutch platein position, and since the ribs engage the clutch plate at theperipheral edge of the clutch plate, the maximum torqueis applied to thedrum or plate. Moreover, this meth- 0d of lockingthe clutch plateto thedrumpermits quick and easy assembly of the clutch with the drum.

The design of the drum hub is such thatit acts not only as a thrustsupport for the clutch plate, but as a bearing for the drum. It providesadditional bearing space without. increasing the overall length of thedrum.

The design of the overload clutch provides a number of advantages. Theclutch plate, being keyed to the drum at the'periphery of the plate,instead of at the center thereof, provides a maximum torque in thedriving of the drum. The embossments on the clutch plate. are designedto give maximum holding power when the plateis engaged with the clutchspring, yet permit easy disengagement of the clutch plate and springwhen excessive torque forces the clutch spring to become disengaged. Theclutch spring is highly effective in its action due tothe fact that ithas a multiplicity of spring fingers which act independently of eachother on the clutch plate. The embossments on the fingers are designedto nest completely in the embossments in the clutch plate, therebyproviding maximum holding qual- D ities. When the embossments on theclutch spring are disengaged from those on the clutch plate, they act ina manner similar to balls, providing a low friction engagement with thesurface of the clutch plate, riding easily over the latter.

The mounting of the clutch spring on the threaded sleeve @8 permits thepressure of the clutch spring against the clutch plate to be varied, andadjusted to slip at a predetermined torque. This adjustability featurealso permits compensation for wear and other variable factors:

Since the pressure of the clutch spring is transmitted to the drumthrough the sleeve 63, the stresses are confined to the hub of the drumand are not distributed to the drum cover. The clutch can be easilyadjusted by means of a torque wrench to any desired degree of pressurebefore the clutch and drum assembly is mounted on the cover plate. Thejam nut 53 provides a positive locking of the adjustment.

It will also be noted that the design of the parts is such as to deliverthe cable, when unwound from the drum, in a straight line from the axisof the cable drum, that the cable groove is formed by assembly of thedrum and drum cover, and that the contour along the cable groove is suchas to preclude breakage of the molded parts.

It will be further noted that the cable groove is square incross-section, and that the width the square section :is slightlygreater than the 7 diameter ofthe cable. -By thus having a round cablesliding in a square groove, friction losses are negligible, due to thecontacting surfaces being minute, as evidenced by inscribing a circle ina square.

Although a cable of the type embodying a loose internal stiffening wireis disclosed, it will be understood that the cable may have externallywound wire of various shapes and winding pitches to engagecorrespondingly molded serrations in the cable groove, or may be of anyother type, such as flat wire, plastic rod, etc.

The pear or banjo shape of the antenna reel and easing provides asymmetrical design which permits the reel to be mounted in theautomobile at either the right or left side. All of the moving ofelectrically functioning parts below the mounting insulators are totallyenclosed and shielded, and the design of the mounting bracket and mannerof fastening it to the shielding tube and casing eliminates all strainsat the junction of the casing and tube. The antenna supporting sleeve isrigidly fastened to the mounting bracket, and the supporting bracketprovides a method of grounding the lead-in shield braid by solderingthrough a hole in the support sleeve. This prevents breakage of theshield braid at the soldered joint, due to the braid being supportedbeyond the soldered joint.

The method of connecting the parts of the casing, as shown in Fig. 14,permits easy assembly and disassembly by a simple pivotal movement ofthe casing part I relatively to the casing part 3.

It is to be understood that the form of my invention, herewith shown anddescribed, is to be taken as a preferred example of the same, and thatvarious changes in the shape, size and arrangement of parts may beresorted to, without departing from the spirit of my invention, or thescope of the subjoined claims.

Having thus described my invention, I claim:

1. An antenna reel, comprsing a drum having an annular groove therein,the walls of said groove having serrations extending into the groove andextending also longitudinally for subtantially the entire depth of thegroove, and a cable adapted to be coiled within said groove, said cableformed of convolutions of wire, said serrations adapted to enter thespaces between said convolutions and frictionally engaging the cable tofacilitate winding and unwinding of the cable from the drum.

2. A reel antenna, as defined in claim 1, in which said serrationsextend in lines substantially parallel with the axis of the drum.

3. A reel antenna, comprising a molded onepiece drum consisting ofspaced annular walls defining a cable groove therebetween, said wallsbeing interconnected at one end to close said groove, a cable coiledwithin said groove and adapted to be fed from the open end of saidgroove, said cable formed of convolutions of wire, the faces of saidwalls provided with serrations adapted to enter the spaces between saidconvolutions for frictionally engaging said cable during winding andunwinding thereof, said serration extending axially of the drum fromsubstantially the closed end to the open end of the groove.

4. A reel antenna, as defined in claim 3, in which serrations areparallel with each other and extend in lines substantially parallel withthe axis of the drum.

5. A reel antenna comprising a molded onepiece drum consisting of spacedinner and outer annular walls defining a cable groove therebetween, saidwalls being interconnected at one end to close said groove, said drumhaving a web extending across the inner wall adjacent the open end ofsaid groove, a drive shaft extending through the center of said drum,and a clutch mounted on said shaft and disposed in its en tirety withinthe space between said web and the closed end of said groove.

6. A reel antenna comprising a molded onepiece drum consisting of spacedinner and outer annular walls defining a cable groove therebetween,reinforcing ribs extending radiallyinwardly from said inner wall, adrive shaft extending centrally through said drum, and a clutch mountedon said shaft, said clutch comprising a clutch plate interengaged withsaid ribs.

7. A reel antenna, as defined in claim 6, in which said clutch plate haspheripheral slots into which said ribs extend.

8. A reel antenna, as defined in claim 6, in which said clutch alsoincludes a clutch spring having radial spring arms bearing on saidclutch plate.

9. A reel antenna, as defined in claim 8, in which means are providedfor adjusting the pressure of said clutch spring against said clutchplate.

10. In a reel antenna of the character described, a, clutch comprising aclutch plate having circumferentially spaced cup-shaped embossments, anda clutch spring having similarly spaced cup-shaped embossments adaptedfor nesting in the embossments of said plate, said spring embossmentshaving rounded bottoms.

11. A reel antenna comprising a molded onepiece drum consisting ofspaced inner and outer annular walls defining a cable groovetherebetween, said walls being interconnected at one end to close saidgroove, said drum having a web adjacent its other end provided with ahub, a drive shaft extending through said hub, and a clutch havingdriving and driven components disposed in the space between said web andthe closed end of the drum and closely adjacent said web, whereby theoverall length of the drum is not greater than the overall length of thedrum and said clutch components.

12. A reel antenna. as defined in claim 11, in which one of said clutchcomponents is a clutch plate which bears directly against said hub.

13. A reel antenna comprising a molded onepiece drum consisting ofspaced inner and outer annular walls defining a cable groovetherebetween, said inner wall having reinforcing ribs extending radiallyinwardly therefrom, portions of which terminate in edges which areclosely adjacent said inner wall, a drive shaft extending centrallythrough said drum, and a clutch mounted on said shaft, said clutchcomprising a clutch plate interengaged with said portions of said ribs,whereby a maximum torque in the driving of said drum is eii'ected.

14. A reel antenna, as defined in claim 13, in which said clutch platehas slots extending radially inwardly from the periphery thereof, saidribs extending into said slots, whereby the clutch plate is, in eifect,keyed to the drum.

15. A reel antenna, as defined in claim 14, in which said clutch alsoincludes a clutch spring having radially extending spring arms bearingon said clutch plate.

l6. A reel antenna, as defined in claim 15, in which means are providedfor adjusting the pressure of said spring arms against said clutchplate, said means comprising a nut adjustable along said shaft andbearing on said clutch spring, and a lock nut on said shaft for lockingsaid adjustable nut in adjusted position.

17. A reel antenna of the character described, comprising a rotatabledrum consisting of spaced inner and outer annular Walls defining a cablegroove therebetween, said walls being interconnected at one end to closesaid groove, a, cable coiled within said groove and adapted to be fedfrom the open end of the groove, a non-rotatable drum cover ofpear-shaped contour disposed adjacent and closing the open end of saidgroove, said cover havin a groove therein, a, portion of which is inregistration with the open end of the groove in the drum, and theremaining portion of which extends through the stem portion of the coverin a direction such as to constrain movement of the cable through thecover and out of the cover in a direction which is radial to the drumand intersects the axis of the drum.

18. A reel antenna, as defined in claim 17, in

-.,which the cable is of Jtion, and the portion of the groove in thestem vportion of the cover is of rectangular crosssection, whereby thecable is propelled through circular external crosssecsaid groove withminimum friction.

: THEODORE R. FINKE.

REFERENCES CITED The following references are of record in the fileofthis patent:

UNITED STATES PATENTS Number Name 7 Date 596,580 Dvork Jan. 4, 18981,805,619 Fuller May 19, 1931 2,130,993 Dubilier Sept. 20, 19382,274,883 Brach Mar. 3, 1942 2,327,163 Barrett Aug. 17, 1943 2,329,404Mace Sept. 14, 1943 2,341,401 White Feb. 8, 1944 2,343,684 Mace Mar. 7,1944 2,344,490 Brach Mar. '21, 1944 2,496,785 Finneburgh Feb. 7, 1950

